Effects of Eu³⁺ co-doping on the structural and optical properties of Ce³⁺ doped ZnO powder synthesized by chemical bath deposition method

In this study undoped, Ce³⁺-, Eu³⁺- doped and Ce³⁺: Eu³⁺ and co-doped ZnO nanopowders were synthesized by the chemical bath deposition (CBD) method. The samples were annealed at 700 °C for 2 h using an open furnace. The aim in this study was to investigate the energy transfer processes between Ce³⁺ and Eu³⁺ ions into ZnO powders. The X-Ray diffraction results indicated an increase in the crystallite sizes while scanning electron microscopy shown aggregation for the Ce³⁺: Eu³⁺ co-doped ZnO nanopowders. Ultraviolet–visible spectra exhibited red and blue shift in the Ce³⁺-, Eu³⁺ doped and Ce³⁺: Eu³⁺ co-doped ZnO nanopowders, respectively. The emission peaks at 582, 617, 659 and 705 nm are attributed to Eu³⁺ intra-4f transitions of ⁵D₀ →⁷F₁ ⁵D₀ →⁷F₂ ⁵D₀ →⁷F₃ and ⁵D₀ →⁷F₄ when excited by 465, 534 and 582 nm after co-doping. The chromaticity diagram show colour co-ordination in the orange vertex.